Apparatus and method for masking residual visible light from an infrared emission source

ABSTRACT

A light masking system for a vehicle includes: a printed circuit board (PCB); at least one infrared (IR) light source disposed on a first surface of the PCB and configured to emit a first predetermined wavelength range of light; at least one masking light source disposed on the first surface of the PCB proximal to the IR light source and configured to emit a second predetermined wavelength range of light, wherein a portion of the emitted first predetermined wavelength range of light of the IR light source includes visible light; and the emitted second predetermined wavelength range of light of the at least one masking light source masks the emitted visible light from the first predetermined wavelength range of the at least one IR light source.

INCORPORATION BY REFERENCE

This application is a continuation of U.S. application Ser. No.16/670,945 filed Oct. 31, 2019 (US202000370723), which claims thebenefit of U.S. Provisional Application No. 62/920,920 filed on May 23,2019, the entire contents of which are incorporated herein by reference.

BACKGROUND

The “background” description provided herein is for the purpose ofgenerally presenting the context of the disclosure. Work of thepresently named inventors, to the extent it is described in thisbackground section, as well as embodiments of the description which maynot otherwise qualify as prior art at the time of filing, are neitherexpressly or impliedly admitted as prior art against the presentinvention.

An imaging system for a vehicle including an image sensor having atwo-dimensional array of photosensitive pixels that includes at leastone sub-array having first, second, third, and fourth photosensingpixels is described in US patent 20150092059A1 entitled “Imaging Systemfor Vehicle”, the entire disclosure of which is incorporated herein byreference. A polymeric multilayered film which reflects wavelengths oflight in the infrared region of the spectrum while being substantiallytransparent to wavelengths of light in the visible spectrum without theeffects of visibly perceived iridescent color is provided is describedin U.S. Pat. No. 5,233,465 entitled “Visibly Transparent InfraredReflecting Film with Color Masking”, the entire disclosure of which isincorporated herein by reference. A vehicle light that can be used, forexample, in a headlamp assembly for a headlight projection system foruse with forward illumination, comprising a reflector and a light sourceoperatively mounted with the reflector is described in US patent20090052200A1 entitled “Single Source Visible and IR Vehicle Headlamp”,the entire disclosure of which is incorporated herein by reference.

Near Infra-Red (NIR) light is important to use with autonomous vehiclesfor use in low light level areas for image/obstacle detection. Locationof these illumination systems on the vehicle is important as regulationsexist for nearly the entire vehicle when dealing with visible lightemission. FIG. 1A shows an example spectrum of an NIR light emittingdiode (LED) with a centroid peak of 850 nm. It may be appreciated thatwhile LEDs are described throughout, other light sources andilluminators may be used. Emission from NIR LEDs may have a portion ofthe emission wavelength range located within the visible portion of theelectromagnetic spectrum, making the NIR LEDs at least partially visibleto a human eye, for example emitting a red glow. As shown in FIG. 1A,this may include, for example, emission below 780 nm. This partialvisibility of the NIR LED may conflict with light regulations, forexample Federal Motor Vehicle Safety Standard 108.

Attempts to block the NIR LED emission using filtering films may blockonly a portion of the residual visible light emitted by the NIR LED.Furthermore, filtering films may impact sensitivity of sensors indetecting NIR signals reflected off of obstacles. In another attempt toreduce emission in the visible range, 940 nm NIR LEDs may be used thathave lower emission below 780 nm. However, performance of said 940 nmNIR LEDs may not be sufficient given hardware sensitivities. That is,sensitivity of sensors to 940 nm NIR LEDs may be approximately half assensitive compared to detecting 850 nm NIR LEDs. In such a situation,the sensitivity of 940 nm NIR LEDs may be difficult to distinguish fromnoise levels and 850 nm NIR LEDs may be used to overcome saidperformance issues.

Thus, a system and method of masking the visible light emission of NIRLEDs is desired. A solution described herein to comply with regulationsincludes masking the NIR LED emission by employing other light emittingsources on the vehicle that emit at a predetermined intensity.

SUMMARY

The present disclosure relates to a light masking system for a vehicle,including: a printed circuit board (PCB); at least one infrared (IR)light source disposed on a first surface of the PCB and configured toemit a first predetermined wavelength range of light; at least onemasking light source disposed on the first surface of the PCB proximalto the IR light source and configured to emit a second predeterminedwavelength range of light, wherein a portion of the emitted firstpredetermined wavelength range of light of the IR light source includesvisible light; and the emitted second predetermined wavelength range oflight of the at least one masking light source masks the emitted visiblelight from the first predetermined wavelength range of the at least oneIR light source.

The present disclosure additionally relates to a method of masking IRlight in a light masking system for a vehicle, including setting, viaprocessing circuitry, a predetermined emission luminous intensity of atleast one IR light source disposed on a first surface of a printedcircuit board (PCB), the IR light source configured to emit apredetermined wavelength range of light; setting, via processingcircuitry, a predetermined emission luminous intensity of at least onemasking light source disposed on the first surface of the printedcircuit board (PCB) and proximal to the at least one IR light source,wherein the predetermined emission luminous intensity of the at leastone masking light source is greater than the predetermined emissionluminous intensity of the at least one IR light source; determining, viaprocessing circuitry, when the vehicle is within a predetermined rangeof other vehicles; and adjusting, via processing circuitry, thepredetermined emission luminous intensity of the at least one IR lightsource in response to being within a predetermined range of the othervehicles, wherein a portion of the emitted predetermined wavelengthrange of light of the IR light source includes visible light.

The present disclosure additionally relates to a method of masking IRlight for a vehicle, including: locating at least one IR light sourceproximal to a visible light source on the vehicle, wherein the at leastone IR light source is configured to emit a predetermined wavelengthrange of light with a predetermined luminous intensity; the visiblelight source is configured to emit a predetermined wavelength range oflight in the visible spectrum with a predetermined luminous intensity; aportion of the emitted predetermined wavelength range of light of the IRlight source includes visible light; the emitted predeterminedwavelength range of light of the visible light source masks the emittedvisible light from the predetermined wavelength range of the at leastone IR light source.

The foregoing paragraphs have been provided by way of generalintroduction, and are not intended to limit the scope of the followingclaims. The described embodiments, together with further advantages,will be best understood by reference to the following detaileddescription taken in conjunction with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

A more complete appreciation of the disclosure and many of the attendantadvantages thereof will be readily obtained as the same becomes betterunderstood by reference to the following detailed description whenconsidered in connection with the accompanying drawings, wherein:

FIG. 1A is an example spectrum of an NIR light emitting diode (LED) witha centroid peak of 850 nm, according to an exemplary embodiment of thepresent disclosure;

FIG. 1B shows a vehicle including a computer with processing circuitry,sensors, and cameras, according to an embodiment of the presentdisclosure;

FIG. 2A is a perspective view of a light masking system, according to anexemplary embodiment of the present disclosure;

FIG. 2B is a top-down view of a light masking system, according to anexemplary embodiment of the present disclosure;

FIG. 2C is a profile view of a light masking system, according to anexemplary embodiment of the present disclosure;

FIG. 3 is a schematic with measurements for a light masking system,according to an exemplary embodiment of the present disclosure;

FIG. 4 is a flow chart for a method of adaptively masking an IR LEDemission, according to an exemplary embodiment of the presentdisclosure;

FIG. 5 is a flow chart for a method of adaptively masking an IR LEDemission with consideration for other vehicle proximity, according to anexemplary embodiment of the present disclosure;

FIG. 6 is a flow chart for a method of locating an IR LED on a vehicle,according to an exemplary embodiment of the present disclosure;

FIG. 7 is a block diagram of a hardware description of a computer;according to an exemplary embodiment of the present disclosure;

FIG. 8 is a schematic diagram of an exemplary data processing system,according to an exemplary embodiment of the present disclosure; and

FIG. 9 is an implementation of a central processing unit, according toan exemplary embodiment of the present disclosure.

DETAILED DESCRIPTION

The description set forth below in connection with the appended drawingsis intended as a description of various embodiments of the disclosedsubject matter and is not necessarily intended to represent the onlyembodiment(s). In certain instances, the description includes specificdetails for the purpose of providing an understanding of the disclosedsubject matter. However, it will be apparent to those skilled in the artthat embodiments may be practiced without these specific details. Insome instances, well-known structures and components may be shown inblock diagram form in order to avoid obscuring the concepts of thedisclosed subject matter.

Reference throughout the specification to “one embodiment” or “anembodiment” means that a particular feature, structure, characteristic,operation, or function described in connection with an embodiment isincluded in at least one embodiment of the disclosed subject matter.Thus, any appearance of the phrases “in one embodiment” or “in anembodiment” in the specification is not necessarily referring to thesame embodiment. Further, the particular features, structures,characteristics, operations, or functions may be combined in anysuitable manner in one or more embodiments. Further, it is intended thatembodiments of the disclosed subject matter can and do covermodifications and variations of the described embodiments.

It must be noted that, as used in the specification and the appendedclaims, the singular forms “a,” “an,” and “the” include plural referentsunless the context clearly dictates otherwise. That is, unless clearlyspecified otherwise, as used herein the words “a” and “an” and the likecarry the meaning of “one or more.” Additionally, it is to be understoodthat terms such as “top,” “bottom,” “front,” “rear,” “side,” “interior,”“exterior,” and the like that may be used herein, merely describe pointsof reference and do not necessarily limit embodiments of the disclosedsubject matter to any particular orientation or configuration.Furthermore, terms such as “first,” “second,” “third,” etc., merelyidentify one of a number of portions, components, points of reference,operations and/or functions as described herein, and likewise do notnecessarily limit embodiments of the disclosed subject matter to anyparticular configuration or orientation.

Due to the visible light emission of NIR LEDs, said LEDs installed onvehicles may not comply with regulations for visible light emission asit relates to the emission location on the vehicle. For example, a redglow from an NIR LED along the front of the vehicle may not be withinregulation since this may impact other drivers. Thus, a system andmethod to mask the emission of NIR LEDs utilizing other LEDs withpredetermined emission spectra and intensities is described herein.

FIG. 1B shows a vehicle that may include a computer with processingcircuitry, sensors for detecting visible and IR light, and cameras forimage capture, according to an embodiment of the present disclosure.According to regulations, for example SAE J578, a color of tail lightson a rear of the vehicle may be red with a luminous intensity of no lessthan 2 candela (cd), a color of rear side markers on a side and towardsthe rear of the vehicle may be red with a luminous intensity of no lessthan 0.25 cd, a color of front side markers on the side and towards thefront of the vehicle may be amber with a luminous intensity of no lessthan 0.62 cd, and a color of headlights at a front of the vehicle may bewhite.

FIGS. 2A-C show various views of a light masking system 100 for thevehicle, according to an embodiment of the present disclosure. The lightmasking system 100 may include a printed circuit board (PCB) 105, aconductive layer 110, capacitors and resistors 115, at least one IR LED120 (herein referred to as “IR LED 120”), and at least one masking LED125 (herein referred to as “masking LED 125”).

As described herein, when a voltage is applied to the masking LED 125and/or the IR LED 120, a radiant power is emitted with a portion of theradiant power being attributable to wavelengths of electromagneticradiation in the visible spectrum and another portion being attributableto wavelengths of electromagnetic radiation in the infrared spectrum.Thus, herein, luminous intensity refers to an intensity of the visiblelight emitted. When adjusting voltage of the masking LED 125 and/or theIR LED 120, the radiant power as a whole changes and the portionsattributable to the visible spectrum and infrared spectrum changeproportionally.

In an embodiment, the PCB 105 may be a circuit board commonly employedin the art. For example, a single-sided, double-sided, or multi-layeredPCB. The PCB 105 may also be, for example, an integrated circuit (IC)such as an application-specific IC, or a hybrid circuit. The PCB 105 maybe fabricated from typical substrate materials, such as epoxy resinimpregnated with woven glass fiber, FR4, IMS, or sub-mount. Theconductive layer 110 may be disposed on a top surface of the PCB 105 andused to electrically connect components on the top surface, such as thecapacitors and resistors 115. An additional conductive layer 110 may bedisposed on a bottom surface of the PCB 105, and in a multi-layer PCB105, multiple PCB 105 panels (which are insulating) may be stacked inlayers that alternate with layers of the conductive layer 110.

The conductive layer 110 may be formed from a conductive film, such ascopper, silver, gold, aluminum, etc. As shown (not labeled), the PCB 105may include a plurality of vias, such as through-hole vias, blind vias,buried vias, etc. that electrically connect components in or on variouslayers of the PCB 105. For example, a capacitor or resistor 115 on thetop surface may be connected to another component or grounding coatingon the bottom layer via a through-hole via. A power source may supplypower to the PCB 105 and electronic components installed thereon.

In an embodiment, the IR LED 120 may emit electromagnetic radiation(i.e. light) at a centroid peak wavelength of approximately 850 nm witha predetermined radiant intensity. The predetermined radiant intensitymay be determined by myriad factors, including proximity to the maskingLED 125, position on the vehicle, and regulations, for instance. The IRLED 120 may receive a voltage from a power source in order to emitlight. Notably, the power source may vary the supplied current to varythe radiant intensity. For example, the IR LED 120 may be configured toilluminate in a pulsed mode, wherein the IR LED 120 emits light atpredetermined intervals of time and otherwise does not emit light. Thepulsed mode may be of benefit to thermal performance of the IR LED120—the supplied current may be higher (as compared to a steady-stateemitting IR LED 120) in order to achieve higher output at each pulse andthe IR LED 120 is able to cool down between pulses. The pulse modewould, in essence, create an effect of a flashing red light on thevehicle (further lending to the importance of masking said visible lightfrom the IR LED 120).

The emission wavelength of the IR LED 120 may be determined by thesemiconductors used in the fabrication of the IR LED 120. The perceivedoptical properties may be adjusted by altering IR LED 120 packaging,such as a lens. An emitted beam angle of the IR LED 120 light may rangefrom wide to narrow. The emitted beam angle may be determined by anoptional reflector or other optical directional apparatus, a size anddesign criteria of the semiconductors, a distance from the IR LED 120 tothe top of the lens, and a geometry of the lens.

In an embodiment, the IR LED 120 may include a substantiallyhemispherical lens to facilitate emission of light from the IR LED 120.The hemispherical lens may result in a more symmetrical distribution ofthe light. Other shapes for the lens may be contemplated to yieldvarying emission patterns. For example, a planar or parabolic lens maybe used for less symmetrical and more directed light (narrower beamangle) compared to the hemispherical lens.

FIG. 3 shows measurements for the light masking system 100, according toan embodiment of the present disclosure. In an embodiment, more than oneIR LED 120, for example two IR LEDs 120, may be disposed on the topsurface of the PCB 105 and electrically connected via the conductivelayer 110 disposed between the IR LEDs 120 and the PCB 105.

Centers of the two IR LEDs 120 may be separated by a predetermineddistance, for example 8 mm to 16 mm, or 10 mm to 14 mm, or preferably 12mm. The lens of the IR LED 120 may have a radius of, for example, 1.5mm. The light masking system 100 may have a length of 25 mm, a width of13.8 mm, and a thickness of 1.6 mm (for the PCB 105). A pin header maybe attached to the bottom of the PCB 105 that electrically connects thelight masking system 100 to auxiliary components on the vehicle. The pinheader may also include a heat sink configured to thermally contact theIR LED 120 and masking LED 125 to facilitate transfer away of heatgenerated by either light source.

In an embodiment, the masking LED 125 may emit a predeterminedwavelength of visible light. For example, the masking LED 1235 may emitred light with a centroid peak wavelength of 700 nm. For example, themasking LED 1235 may emit amber/yellow light with a centroid peakwavelength of 600 nm. For example, the masking LED 1235 may emit whitelight with a broadband spectrum across the visible range, such as from350 nm to 750 nm.

In an embodiment, one masking LED 125 may be disposed on the top surfaceof the PCB 105 between the two IR LEDs 120 and electrically connected toother components via the conductive layer 110 disposed between themasking LED 125 and the PCB 105. A center of the masking LED 125 may beseparated from the center of the two IR LEDs 120 by a predetermineddistance, for example 8 mm to 4 mm, or 7 mm to 5 mm, or preferably 6 mm.

In an embodiment, the masking LED 125 may be a monochromatic LED. Thepredetermined color and a luminous intensity of emitted light of themasking LED 125 may be determined by the location of the masking LED 125on the vehicle. For example, the masking LED 125 may be located on theside and towards the front of the vehicle, and the predetermined colormay be amber with a luminous intensity of less than 0.62 cd in order torepresent a side illumination marker and stay within regulations. Inanother example, the masking LED 125 may be located on the rear of thevehicle, and the predetermined color may be red with a luminousintensity of less than 2 cd in order to represent a rearillumination/brake marker and stay within regulations. In anotherexample, the masking LED 125 may be located on the front of the vehicle,and the predetermined color may be white (achromatic). It may beappreciated that the aforementioned examples may be combined on onevehicle wherein one or more of each example's light masking system 100may be installed. In such an example, three different masking LEDs 125may be used in various light masking systems 100 based on the locationof each light masking system 100 on the vehicle.

In an embodiment, the masking LED 125 may be polychromatic andconfigured to emit one or more colors across a broad wavelength spectrumat varying luminous intensities. The masking LED 125 may be programmedto emit a predetermined color at a predetermined luminous intensitybased on the location of the masking LED 125 on the vehicle. In thefollowing examples, a single model of masking LED 125 may be used duringfabrication to install in the light masking system 100, and any lightmasking system 100 may be installed at any location on the vehicle. Forexample, the masking LED 125 may be located on the side and towards thefront of the vehicle, and the programmed emission color may be amberwith a programmed luminous intensity of less than 0.62 candela (cd). Thesame masking LED 125 may be located instead on the rear of the vehicle,and the programmed emission color may be red with a programmed luminousintensity of less than 2 cd. Thus, the same model of masking LED 125 maybe used in either location and programmed according to the location onthe vehicle.

Advantageously, fabrication of the light masking system 100 is easierbecause only a single model of masking LED 125 is installed on the PCB105 and any accidental installations of the incorrect masking system 100at a particular location on the vehicle can be remedied byre-programming the masking LED 125.

Concomitantly, the luminous intensity of emitted light of the IR LED 120may also be determined by the location of the IR LED 120 on the vehicle.In an embodiment, the IR LED 120 may emit at a radiant intensity lessthan (but nearly equal to) the luminous intensity of the proximalmasking LED 125 in the same masking light system 100. For example, theIR LED 120 may emit at approximately 80% the radiant intensity as theproximal masking LED 125. For the masking LED 125 located on the sideand towards the front of the vehicle, the predetermined luminousintensity of the masking LED 125 may be 0.60 cd and the predeterminedradiant intensity of the IR LED 120 may be 0.48 cd. Advantageously, thegreater luminous intensity of the masking LED 125 effectively masks theemission of the IR LED 120 while still resembling the same function ofother lighting in the same area on the vehicle. That is to say, anobserver (with visible light sensitivity) viewing the vehicle from anyperspective may not see the visible light emission from the IR LED 120since the masking LED 125 emission may sufficiently overpower theemission from the IR LED 120. Therefore, a red light emission from theIR LED 120 disposed proximal to the headlights, for instance, may notappear red to the observer since emission from the masking LED 125 (e.g.a white light) may overpower the red light. This may be coupled withemission from the headlights with, for example, additional white light.

It may be appreciated that the current supplied to the masking LED 125and IR LED 120 may be adjusted in order to ensure that the emission ofthe masking LED 125 is sufficient to mask the emission of the IR LED 120as determined by regulations at various vehicle locations and radiantintensities. To remain in compliance with FMVSS108 Section 6.2.1Impairment (in original document F.R. Vol. 41 No. 164-23.081976), “Noadditional lamp, reflective device, or other motor vehicle equipment ispermitted to be installed that impairs the effectiveness of lightingequipment required by this standard.” The combined radiant intensity ofthe masking LED 125 and IR LED 120 must not cause impairment, andtherefore, are not to exceed the legal minimum requirements of nearbyexisting lighting functions on the vehicle. In an embodiment, to ensurethat the IR LED 120 complies with the strictest regulation, a singlemodel of the IR LED 120 may be installed in all light masking systems100. In an embodiment, the maximum radiant intensity may include thetotal output of both the IR LED 120 and the masking LED 125. Forexample, according to SAE J578, the IR LED 120 may emit at a maximumradiant intensity of less than 0.25 cd as set forth for the side rearillumination marker. For example, according to FMVSS108's Table X: SideMarker Lamp Photometry Requirements, the IR LED 120 may emit at amaximum radiant intensity of less than 0.25 cd and 0.62 cd for the rearand front side markers, respectively.

In an embodiment, the light masking system 100 may include two IR LEDs120 and one masking LED 125 installed on the PCB 105, wherein themasking LED 125 may be disposed between the two IR LEDs 120 andseparated by, for example, 6 mm between the center of the masking LED125 and each of the two IR LEDs 120. The two IR LEDs 120 may be disposedon opposite sides of the masking LED 125 and separated by 12 mm. Asingle model of the IR LED 120 may be installed across all light maskingsystems 100 on the vehicle. The IR LED 120 may emit with a centroid peakwavelength of 850 nm when pulsed at 10 Hz with regulatory-complyingintensity, wherein the radiant intensity of the IR LED 120 emission inthe visible spectrum is masked by the luminous intensity of the maskingLED 125, wherein the luminous intensity of the masking LED 125 isgreater than the radiant intensity of the IR LED 120 emission in thevisible spectrum and within regulation guidelines. It may be appreciatedthat other dimensions and number of masking LEDs 125 per IR LED 120 invary arrangements may be implemented such that the radiant intensity ofthe IR LED 120 is sufficiently masked by the luminous intensity of themasking LEDs 125. In an embodiment, the camera or sensors may detect thepresence of other vehicles within a predetermined range of the [main]vehicle and the radiant intensity of the IR LED 120 emission may beadjusted. That is, the IR LED 120 may be configured to emit at multiplepower levels based on the proximity of other vehicles to the vehicle.For simplicity, a low and a high emission setting for the IR LED 120 aredescribed, but multiple levels of output may be contemplated (e.g. afirst setting, a second setting, a third setting, etc.). The camera orsensors may determine other vehicles are within the predetermined rangeof the main vehicle. For example, the predetermined range may be a 250meter radius (inclusive). All of the IR LEDs 120 on the main vehicle mayemit with a centroid wavelength of 850 nm and at the low setting of cdwhen the camera or the sensors determine the other vehicles are insidethe predetermined range. Upon the other vehicles exiting thepredetermined range of the main vehicle, the processing circuitry mayincrease the radiant intensity of the IR LEDs' 120 emission to the highsetting in the range of, for example, 0.26 to 10 cd. The increasedradiant intensity of the IR LEDs 120 may be achieved by, for example,increasing the power to the IR LEDs 120. Even though the increasedradiant intensity of the IR LEDs' 120 emission may be greater than theluminous intensity of the proximal masking LED 125 emission, the portionof the visible light emitted by the IR LEDs 120 may not be detected bythe other vehicles because the other vehicles are not within range ofthe main vehicle. Advantageously, the increase in radiant intensity ofthe IR LEDs 120 emission may allow for more sensitive detection of theIR light by the sensors on the main vehicle and the IR light may travela greater distance (as compared to when at 0.25 cd) in order to detectobjects farther ahead in the path of the main vehicle. Thus, theincreased power of the IR LEDs 120 on the high setting allows the mainvehicle to detect objects sooner and provides additional time to takecorrective action and keep the main vehicle occupant(s) safe. Upondetecting the other vehicles have entered the predetermined range of themain vehicle, the radiant intensity of the IR LEDs' 120 emission may bedecreased to the initial low setting of 0.25 cd to remain belowregulation guidelines.

In an embodiment, the camera may be configured to capture images and theprocessing circuitry may be configured to analyze the image to recognizeobjects, for example the other vehicles, and determine a brightness andcolor of any light sources from the other vehicles. For example, thecamera may capture a rear of another vehicle in front of the vehicle andthe processing circuitry may determine the color of the lights are red(for tail lights) and above a predetermined brightness threshold toindicate the other vehicle is within range of the main vehicle. Thus,the radiant intensity of the IR LED 120 is adjusted to the low setting.

In an embodiment, the processing circuitry may determine the averagebrightness of the light sources over a predetermined duration. Forexample, the predetermined duration may be 5 seconds, and the extendedwindow of time over which the average brightness is determined mayadvantageously filter out instances of bursts of brightness from otherlight sources that lead to false-positive readings of other vehiclesbeing within range. The main vehicle may be traveling on a highway withperiodic overhead light and the brightness from the overhead lights mayincorrectly trigger the processing circuitry to adjust the radiantintensity of the IR LED 120 to the low setting. Thus, the 5 secondwindow over which the average brightness is determined may reduce thebrightness contributed to the reading from the overhead lighting. Inaddition, the image recognition from the camera may also be used incombination with the brightness reading to determine that the lightsource is from the overhead lighting instead of another vehicle.

In an embodiment, the sensors may be configured to detect IR lightemitted from the IR LEDs 120 that reflect off of objects proximal to themain vehicle and return to the sensors. The processing circuitry may beconfigured to determine a delay between the emission of the IR light anddetection by the sensors and, based on the delay, determine the distanceof the object from the main vehicle. Based on the distance of the objectfrom the main vehicle, the processing circuitry may adjust the radiantintensity of the IR LEDs 120.

It may be appreciated that the brightness determination and imagerecognition by the camera may be used separately or in combination withthe distance determination by the sensors to adjust the radiantintensity of the IR LEDs 120.

In an embodiment, the camera or sensors may detect the presence of othervehicles within the predetermined range of the main vehicle relative tothe orientation of the main vehicle. Upon determining the presence andorientation of the other vehicles relative to the main vehicle, theprocessing circuitry may adjust the emission radiant intensity of asubset of the IR LEDs 120. For example, the camera or sensors maydetermine the other vehicles are outside the predetermined range in afront direction of the main vehicle. Upon determining the frontdirection of the main vehicle is clear of the other vehicles, theprocessing circuitry may increase the radiant intensity of the IR LEDs120 facing the front direction to the high setting. The IR LEDs 120 inthe light masking systems 100 installed at the front of the vehicle(white headlights) and on the side towards the front of the vehicle(amber side markers) may be adjusted to the high setting, for instance,while those installed at the rear of the vehicle (red tail lights) andon the side towards the rear of the vehicle (red side markers) remain inthe low setting. Again, the increase in emission radiant intensity ofthe IR LEDs 120 facing the front direction may allow for more sensitivedetection of the IR light by the front-facing sensors on the mainvehicle and the IR light may travel a greater distance (as compared towhen at 0.25 cd) in order to detect objects farther ahead in front ofthe main vehicle. In another example, the processing circuitry maydetermine the other vehicles are outside the predetermined range in arear direction of the main vehicle.

Upon determining the rear direction of the main vehicle is clear of theother vehicles, the processing circuitry may increase the radiantintensity of the IR LEDs 120 facing the rear direction to the highsetting. The IR LEDs 120 in the light masking systems 100 installed atthe rear of the vehicle (red tail lights) and on the side towards therear of the vehicle (red side markers) may be adjusted, for instance,while those installed at the front and on the side towards the front ofthe vehicle remain in the low setting. The increase in emission radiantintensity of the IR LEDs 120 facing the rear direction may allow formore sensitive detection of the IR light by the rear-facing sensors onthe main vehicle and the IR light may travel a greater distance (ascompared to when at 0.25 cd) in order to detect objects farther backbehind the main vehicle. The rear-facing sensors may detect othervehicles approaching from the rear direction and take pre-emptive actionto warn the approaching other vehicles upon determining a speed of theapproaching other vehicle is too fast. For example, in response todetermining the approaching other vehicle is traveling too fast, theprocessing circuitry may be configured to flash the rear-facing maskingLEDs 125 and other tail lights, activate a horn on the vehicle, or acombination thereof to warn the approaching other vehicle. Upondetecting the other vehicles have entered the predetermined range of themain vehicle in either direction, the emission radiant intensity of therespective IR LEDs 120 may be decreased to the initial 0.25 cd to remainbelow regulation guidelines.

In an embodiment, the IR LED 120 may be located proximal to a lightsource on the vehicle. That is to say, the existing functional LEDs andlight sources on the vehicle may be utilized to mask the emission of theIR LED 120. For example, the IR LED 120 may be installed on the lightmasking system 100 and the light masking system 100 may be installedproximal to the head light of the vehicle. The emission luminousintensity of the head lights may be sufficient to mask the emission ofthe proximal IR LED 120. In another example, the IR LED 120 may beinstalled as part of the head light assembly and not as part of thelight masking system 100. It may be appreciated that the IR LED 120 maybe incorporated into other existing light sources on the vehicle havingsufficient emission luminous intensity.

FIG. 4 shows a flow chart for a method of adaptively masking the IR LED120 emission, according to an embodiment of the present disclosure. Instep S401, the radiant intensity of the IR LED 120 is set to the lowemission setting, for example 0.25 cd. In step S403, the processingcircuitry and sensors determine if other vehicles are within range ofthe main vehicle. In optional step S405, the low emission setting ismaintained if other vehicles are within range of the main vehicle. Instep S407, the radiant intensity of the IR LED 120 is set to the highemission setting, for example 10 cd, if other vehicles are not withinrange of the main vehicle. In step S409, processing circuitry andsensors determine if the vehicle is still powered on. The method repeatsback to step S403 if the vehicle is on, otherwise the method ends andthe lights are turned off.

FIG. 5 shows a flow chart for a method of adaptively masking the IR LED120 emission with consideration for other vehicle proximity, accordingto an embodiment of the present disclosure. In step S501, the radiantintensity of the IR LED 120 is set to the low emission setting, forexample 0.25 cd. In step S503, the processing circuitry and sensorsdetermine if other vehicles are within range of the main vehicle. Instep S505, the radiant intensity of the IR LED 120 is set to the highemission setting, for example 10 cd, if other vehicles are not withinrange of the main vehicle.

If the other vehicles are present, the method proceeds to step S507,wherein processing circuitry and sensors determine if the other vehiclesare in range in front of the main vehicle. In step S509, the radiantintensity of the front-facing IR LEDs 120 is set to the high emissionsetting, for example 10 cd, if the other vehicles are not detected infront of the main vehicle. In step S511, the radiant intensity of thefront-facing IR LEDs 120 is set to the low emission setting (ormaintained at the low emission setting), for example 0.25 cd, if theother vehicles are detected in front of the main vehicle.

In step S513, processing circuitry and sensors determine if the othervehicles are in range in the rear direction of the main vehicle. In stepS515, the radiant intensity of the rear-facing IR LEDs 120 is set to thehigh emission setting, for example 10 cd, if the other vehicles are notdetected towards the rear direction of the main vehicle. In step S517,the radiant intensity of the rear-facing IR LEDs 120 is set to the lowemission setting (or maintained at the low emission setting), forexample 0.25 cd, if the other vehicles are detected towards the rear ofthe main vehicle.

In step S521, processing circuitry and sensors determine if the othervehicles are in range in the side direction of the main vehicle. In stepS523, the radiant intensity of the side-facing IR LEDs 120 is set to thehigh emission setting, for example 10 cd, if the other vehicles are notdetected towards the side direction of the main vehicle. In step S525,the radiant intensity of the side-facing IR LEDs 120 is set to the lowemission setting (or maintained at the low emission setting), forexample 0.25 cd, if the other vehicles are detected towards the side ofthe main vehicle.

In step S519, processing circuitry and sensors determine if the vehicleis still powered on. The method repeats back to step S503 if the vehicleis on, otherwise the method ends and the lights are turned off.

FIG. 6 shows a flow chart for a method of locating the IR LED 120 on thevehicle, according to an embodiment of the present disclosure. In stepS601, the IR LED 120 is located proximal to any existing light source onthe vehicle. For example, within 6 mm of the existing light source.

In summary, an advantage of the present disclosure is the ability forthe light masking system 100 to be located at any predetermined locationon the vehicle. The light masking system 100 utilizes an IR imagingsystem (cameras, sensors, and the IR LEDs 120) and the masking LED 125to mask only the visible light emitted from the IR LED 120, thusallowing tunability of the NIR LED 120 location to anywhere on thevehicle. The location of the IR LED 120 is sufficiently proximal to themasking LED 125 wherein the masking LED 125 is constantly emittinglight. For example, during the day the supplemental light source may bea daytime running headlight emitting white light having a predeterminedluminous intensity to mask the NIR LED partial visible light emission.For example, at night the supplemental light source may be a tail lightemitting red light having a predetermined luminous intensity to mask theNIR LED partial visible light emission.

FIG. 7 is a block diagram of a hardware description of a computer 2400used in exemplary embodiments. In the embodiments, computer 2400 can bea desk top, laptop, or server.

In FIG. 7 , the computer 2400 includes a CPU 2401 which performs theprocesses described herein. The process data and instructions may bestored in memory 2402. These processes and instructions may also bestored on a storage medium disk 2404 such as a hard drive (HDD) orportable storage medium or may be stored remotely. Further, the claimedadvancements are not limited by the form of the computer-readable mediaon which the instructions of the inventive process are stored. Forexample, the instructions may be stored on CDs, DVDs, in FLASH memory,RAM, ROM, PROM, EPROM, EEPROM, hard disk or any other informationprocessing device with which the computer 2400 communicates, such as aserver or computer.

Further, the claimed advancements may be provided as a utilityapplication, background daemon, or component of an operating system, orcombination thereof, executing in conjunction with CPU 2401 and anoperating system such as Microsoft® Windows®, UNIX®, Oracle® Solaris,LINUX®, Apple macOS® and other systems known to those skilled in theart. In order to achieve the computer 2400, the hardware elements may berealized by various circuitry elements, known to those skilled in theart. For example, CPU 2401 may be a Xenon® or Core® processor from IntelCorporation of America or an Opteron® processor from AMD of America, ormay be other processor types that would be recognized by one of ordinaryskill in the art. Alternatively, the CPU 2401 may be implemented on anFPGA, ASIC, PLD or using discrete logic circuits, as one of ordinaryskill in the art would recognize. Further, CPU 2401 may be implementedas multiple processors cooperatively working in parallel to perform theinstructions of the inventive processes described above.

The computer 2400 in FIG. 7 also includes a network controller 2406,such as an Intel Ethernet PRO network interface card from IntelCorporation of America, for interfacing with network 2424. As can beappreciated, the network 2424 can be a public network, such as theInternet, or a private network such as LAN or WAN network, or anycombination thereof and can also include PSTN or ISDN sub-networks. Thenetwork 2424 can also be wired, such as an Ethernet network, or can bewireless such as a cellular network including EDGE, 3G and 4G wirelesscellular systems. The wireless network can also be WiFi®, Bluetooth®, orany other wireless form of communication that is known.

The computer 2400 further includes a display controller 2408, such as aNVIDIA® GeForce® GTX or Quadro® graphics adaptor from NVIDIA Corporationof America for interfacing with display 2410, such as a Hewlett Packard®HPL2445w LCD monitor. A general purpose I/O interface 2412 interfaceswith a keyboard and/or mouse 2414 as well as an optional touch screenpanel 2416 on or separate from display 2410. General purpose I/Ointerface 2412 also connects to a variety of peripherals 2418 includingprinters and scanners, such as an OfficeJet® or DeskJet® from HewlettPackard.

The general purpose storage controller 2420 connects the storage mediumdisk 2404 with communication bus 2422, which may be an ISA, EISA, VESA,PCI, or similar, for interconnecting all of the components of thecomputer 2400. A description of the general features and functionalityof the display 2410, keyboard and/or mouse 2414, as well as the displaycontroller 2408, storage controller 2420, network controller 2406, andgeneral purpose I/O interface 2412 is omitted herein for brevity asthese features are known.

FIG. 8 is a schematic diagram of an exemplary data processing system.The data processing system is an example of a computer in which code orinstructions implementing the processes of the illustrative embodimentscan be located.

In FIG. 8 , data processing system 2500 employs an applicationarchitecture including a north bridge and memory controller hub (NB/MCH)2525 and a south bridge and input/output (I/O) controller hub (SB/ICH)2520. The central processing unit (CPU) 2530 is connected to NB/MCH2525. The NB/MCH 2525 also connects to the memory 2545 via a memory bus,and connects to the graphics processor 2550 via an accelerated graphicsport (AGP). The NB/MCH 2525 also connects to the SB/ICH 2520 via aninternal bus (e.g., a unified media interface or a direct mediainterface). The CPU 2530 can contain one or more processors and even canbe implemented using one or more heterogeneous processor systems.

FIG. 9 illustrates an implementation of CPU 2530. In one implementation,an instruction register 2638 retrieves instructions from a fast memory2639. At least part of these instructions are fetched from aninstruction register 2638 by a control logic 2636 and interpretedaccording to the instruction set architecture of the CPU 2530. Part ofthe instructions can also be directed to a register 2632. In oneimplementation the instructions are decoded according to a hardwiredmethod, and in another implementation the instructions are decodedaccording to a microprogram that translates instructions into sets ofCPU configuration signals that are applied sequentially over multipleclock pulses. After fetching and decoding the instructions, theinstructions are executed using an arithmetic logic unit (ALU) 2634 thatloads values from the register 2632 and performs logical andmathematical operations on the loaded values according to theinstructions. The results from these operations can be fed back into theregister 2632 and/or stored in a fast memory 2639. According toembodiments of the disclosure, the instruction set architecture of theCPU 2530 can use a reduced instruction set computer (RISC), a complexinstruction set computer (CISC), a vector processor architecture, or avery long instruction word (VLIW) architecture. Furthermore, the CPU2530 can be based on the Von Neuman model or the Harvard model. The CPU2530 can be a digital signal processor, an FPGA, an ASIC, a PLA, a PLD,or a CPLD. Further, the CPU 2530 can be an x86 processor by Intel or byAMD; an ARM processor; a Power architecture processor by, e.g., IBM; aSPARC architecture processor by Sun Microsystems or by Oracle; or otherknown CPU architectures.

Referring again to FIG. 8 , the data processing system 2500 can includethe SB/ICH 2520 being coupled through a system bus to an I/O Bus, a readonly memory (ROM) 2556, universal serial bus (USB) port 2564, a flashbinary input/output system (BIOS) 2568, and a graphics controller 2558.PCI/PCIe devices can also be coupled to SB/ICH 2520 through a PCI bus2562.

The PCI devices can include, for example, Ethernet adapters, add-incards, and PC cards for notebook computers. The Hard disk drive 2560 andCD-ROM 2566 can use, for example, an integrated drive electronics (IDE)or serial advanced technology attachment (SATA) interface. In oneimplementation the I/O bus can include a super I/O (SIO) device.

Further, the hard disk drive (HDD) 2560 and optical drive 2566 can alsobe coupled to the SB/ICH 2520 through a system bus. In oneimplementation, a keyboard 2570, a mouse 2572, a parallel port 2578, anda serial port 2576 can be connected to the system bus through the I/Obus. Other peripherals and devices can be connected to the SB/ICH 2520using a mass storage controller such as SATA or PATA, an Ethernet port,an ISA bus, a LPC bridge, SMBus, a DMA controller, and an Audio Codec.

A number of implementations have been described. Nevertheless, it willbe understood that various modifications may be made without departingfrom the spirit and scope of this disclosure. For example, preferableresults may be achieved if the steps of the disclosed techniques wereperformed in a different sequence, if components in the disclosedsystems were combined in a different manner, or if the components werereplaced or supplemented by other components.

The foregoing discussion describes merely exemplary embodiments of thepresent disclosure. As will be understood by those skilled in the art,the present disclosure may be embodied in other specific forms withoutdeparting from the spirit or essential characteristics thereof.Accordingly, the disclosure is intended to be illustrative, but notlimiting of the scope of the disclosure, as well as the claims. Thedisclosure, including any readily discernible variants of the teachingsherein, defines in part, the scope of the foregoing claim terminologysuch that no inventive subject matter is dedicated to the public.

What is claimed is:
 1. A light masking system for a vehicle, comprising:a printed circuit board (PCB); processing circuitry; at least oneinfrared (IR) light source disposed on a first surface of the PCB andconfigured to emit a first predetermined wavelength range of light; atleast one masking light source disposed on the first surface of the PCBproximal to the IR light source and configured to emit a secondpredetermined wavelength range of light, wherein a portion of theemitted first predetermined wavelength range of light of the IR lightsource includes visible light; and the emitted second predeterminedwavelength range of light of the at least one masking light source masksthe emitted visible light from the first predetermined wavelength rangeof the at least one IR light source, with the processing circuitryconfigured to adjust luminous intensity of the at least one maskinglight source emission to greater than or equal to radiant intensity ofthe at least one IR light source emission.
 2. The light masking systemof claim 1, wherein the at least one IR light source is a light emittingdiode (LED) with a peak wavelength of 850 nm; and the at least onemasking light source is an LED.
 3. The light masking system of claim 2,wherein the at least one masking light source is configured to emit oneor more peak wavelengths of light spanning a range of 350 nm to 750 nm.4. The light masking system of claim 3, wherein the one or more peakwavelengths of light emitted by the at least one masking light source isbased on a location of the at least one masking light source on thevehicle.
 5. The light masking system of claim 1, wherein the processingcircuitry is configured to adjust, for the at least one IR light sourceemission, a predetermined radiant intensity; and adjust, for the atleast one masking light source emission, a predetermined luminousintensity and a peak wavelength.
 6. The light masking system of claim 5,wherein adjusting the predetermined radiant intensity of the at leastone IR light source emission is based on the location of the at leastone IR light source on the vehicle; and adjusting the predeterminedluminous intensity and the peak wavelength of the at least one maskinglight source emission is based on the location of the at least onemasking light source on the vehicle.
 7. The light masking system ofclaim 6, wherein the at least one IR light source and the at least onemasking light source are located on a side of the vehicle and towards arear of the vehicle; the processing circuitry adjusts the radiantintensity of the at least one IR light source emission to less than 0.25candela (cd); the processing circuitry adjusts the peak wavelength ofthe at least one masking light source emission to a wavelength withinthe range of 700 nm to 750 nm.
 8. The light masking system of claim 6,wherein the at least one IR light source and the at least one maskinglight source are located on a side of the vehicle and towards a front ofthe vehicle; the processing circuitry adjusts the radiant intensity ofthe at least one IR light source emission to less than 0.62 candela(cd); the processing circuitry adjusts the peak wavelength of the atleast one masking light source emission to a wavelength within the rangeof 600 nm to 650 nm.
 9. The light masking system of claim 1, furthercomprising: at least one capacitor and resistor disposed on the firstsurface of the PCB; a conductive layer disposed on the first surface ofthe PCB and configured to electrically connect the at least one IR lightsource, the at least one masking light source, and the at least onecapacitor and resistor to a power source.
 10. The light masking systemof claim 1, the at least one masking light source emits in asubstantially constant emission mode.
 11. A method of masking IR lightin a light masking system for a vehicle, comprising: setting, viaprocessing circuitry, a predetermined emission radiant intensity of atleast one IR light source disposed on a first surface of a printedcircuit board (PCB), the IR light source configured to emit apredetermined wavelength range of light; setting, via processingcircuitry, a predetermined emission luminous intensity of at least onemasking light source disposed on the first surface of the printedcircuit board (PCB) and proximal to the at least one IR light source,wherein the predetermined emission luminous intensity of the at leastone masking light source is greater than the predetermined emissionluminous intensity of the at least one IR light source; determining, viaprocessing circuitry, when the vehicle is within a predetermined rangeof other vehicles; and adjusting, via processing circuitry, thepredetermined emission radiant intensity of the at least one IR lightsource in response to being within a predetermined range of the othervehicles, and in response to determining the other vehicles are outsidea predetermined range, setting the predetermined emission radiantintensity of the at least one IR light source to a high setting, whereina portion of the emitted predetermined wavelength range of light of theIR light source includes visible light.
 12. The method of claim 11,further comprising: adjusting, via processing circuitry, a predeterminedpeak wavelength of the at least one masking light source based on alocation of the at least one masking light source on the vehicle. 13.The method of claim 11, wherein adjusting the predetermined emissionradiant intensity of the at least one IR light source further comprises:in response to determining the other vehicles are within a predeterminedrange, setting the predetermined emission radiant intensity of the atleast one IR light source to a low setting.
 14. The method of claim 11,wherein determining when the vehicle is within a predetermined range ofthe other vehicles further comprises: determining, when the vehicle iswithin a predetermined range of the other vehicles, an orientation ofthe other vehicles relative to the vehicle; and adjusting thepredetermined emission radiant intensity of the at least one IR lightsource further comprises: in response to determining the orientation ofthe other vehicles are not in a front direction of the vehicle, settingthe predetermined emission radiant intensity of a front-facing IR lightsource of the at least one IR light source to a high setting; and inresponse to determining the orientation of the other vehicle is not in arear direction of the vehicle, setting the predetermined emissionradiant intensity of a rear-facing IR light source of the at least oneIR light source to a high setting.
 15. The method of claim 11, whereinthe at least one IR light source and the at least one masking lightsource are located on a side of the vehicle and towards a front of thevehicle; the processing circuitry adjusts the radiant intensity of theat least one IR light source emission to less than 0.62 candela (cd);the processing circuitry adjusts the luminous intensity of the at leastone masking light source emission to greater than or equal to theradiant intensity of the at least one IR light source emission; theprocessing circuitry adjusts the peak wavelength of the at least onemasking light source emission to a wavelength within the range of 600 nmto 650 nm.
 16. The method of claim 11, wherein the at least one IR lightsource is a light emitting diode (LED) with a peak wavelength of 850 nm;and the at least one masking light source is an LED.
 17. The method ofclaim 11, wherein the at least one masking light source emits in asubstantially constant emission mode.
 18. A method of masking IR lightfor a vehicle, comprising: locating at least one IR light sourceproximal to a visible light source on the vehicle, wherein the at leastone IR light source is configured to emit a predetermined wavelengthrange of light with a predetermined radiant intensity; the visible lightsource is configured to emit a predetermined wavelength range of lightin the visible spectrum with a predetermined luminous intensity; aportion of the emitted predetermined wavelength range of light of the IRlight source includes visible light; the emitted predeterminedwavelength range of light of the visible light source masks the emittedvisible light from the predetermined wavelength range of the at leastone IR light source; and adjusting, with a processing circuit, aluminous intensity of the at least one masking light source emission togreater than or equal to a radiant intensity of the at least one IRlight source emission.
 19. The method of claim 18, wherein the at leastone IR light source is integrated into an assembly for the visible lightsource.
 20. The method of claim 18, wherein the at least one maskinglight source emits in a substantially constant emission mode.